Bolander's yampah (Perideridiabolanderi)Distribution: Northeast Oregon and adjacent Idaho, south through eastern Oregon and western Idaho to Nevada and Utah.Habitat: Dry, open, often rocky hillsides, ridges and dry washes in the foothills and high plains.Origin: NativeFlowers: July - August

Gairdner's yampah (Perideridiamontana)Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Colombia to southern California, east to Saskatchewan, South Dakota and New Mexico.Habitat: Woodlands and vernally wet meadows.Origin: NativeFlowers: July-September

Yarrow (Achilleamillefolium)Distribution: Both sides of the Cascades in Washington, from the coast to the alpine; circumboreal; widespread throughout North America.Habitat: Common in open, dry to somewhat moist areas from low to high elevations; tolerant of disturbance.Origin: Both native and introduced populationsFlowers: April-October

Little yellow rattle (Rhinanthusminor)Distribution: Both sides of the Cascades in Washington; Alaska to Newfoundland, south to upper Midwest and New England; circumboreal.Habitat: Moist meadows, forest openings, and roadsides at low to middle elevations, sometimes in subalpine.Origin: NativeFlowers: June-August

Yellow rattle (Rhinanthusminor)Distribution: Both sides of the Cascades in Washington; Alaska to Newfoundland, south to upper Midwest and New England; circumboreal.Habitat: Moist meadows, forest openings, and roadsides at low to middle elevations, sometimes in subalpine.Origin: NativeFlowers: June-August

Northwestern yellow-flax (Sclerolinondigynum)Distribution: East of the Cascades in Washington; Washington south to the Sierra Nevada of California, east to Idaho.Habitat: Meadows and prairies at low to moderate elevations.Origin: NativeFlowers: May-July

Garden yellow-loosestrife (Lysimachiavulgaris)Distribution: Occurring in scattered localities on both sides of the Cascades in Washington; British Columbia to Oregon, east to Montana; widely distributed in eastern North America.Habitat: Uncommon garden escape of moist areas, lake and pond margins, and riparian zones.Origin: Introduced from EuropeFlowers: June-August

Large yellow-loosestrife (Lysimachiapunctata)Distribution: Scattered localities across Washington; British Columbia south Oregon, east to Montana; scattered throughout central and eastern North America.Habitat: Old fields, roadsides and stream banks.Origin: IntroducedFlowers: July-August

Tufted yellow-loosestrife (Lysimachiathyrsiflora)Distribution: Distributed on both sides of the Cascades in Washington; Alaska south to California, eastern North America.Habitat: Swamps, lakes and ditches.Origin: NativeFlowers: May-July

Blunt-leaved yellowcress (Rorippacurvipes)Distribution: Occurring chiefly east of the Cascades in Washington; widely distributed throughout western and central North America.Habitat: Wet areas including streambanks, lake shores, wet meadows, and ditches.Origin: NativeFlowers: May-September

Creeping yellowcress (Rorippasylvestris)Distribution: Known only from Whitman County in Washington; British Columbia south to Oregon, east across North America to the Atlantic Coast.Habitat: Disturbed, moist areas at low to middle elevations.Origin: Introduced from EuropeFlowers: May-August

Spreading yellowcress (Rorippasinuata)Distribution: Occurring in Klickitat County in Washington; British Columbia south to California, east to central North America.Habitat: Wet areas including pond and lake margins, stream banks, and ditches.Origin: NativeFlowers: May-September

Truncate yellowcress (Rorippacurvipes)Distribution: Occurring chiefly east of the Cascades in Washington; widely distributed throughout western and central North America.Habitat: Wet areas including streambanks, lake shores, wet meadows, and ditches.Origin: NativeFlowers: May-September

Western yellowcress (Rorippacurvisiliqua)Distribution: British Columbia to California, east to Montana and NevadaHabitat: Stream banks and moist soil, low to mid-elevations in the mountainsOrigin: NativeFlowers: May - September

Pacific yew (Taxusbrevifolia)Distribution: Alaska to California, east to northern Idaho and northeast OregonHabitat: Open to deep, usually moist forests, sea level to mid-elevations in the mountainsOrigin: NativeCones: September - October

Western yew (Taxusbrevifolia)Distribution: Alaska to California, east to northern Idaho and northeast OregonHabitat: Open to deep, usually moist forests, sea level to mid-elevations in the mountainsOrigin: NativeCones: September - October